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        <td class="header">&nbsp; SRGR Operator</td>
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<h3>Slant Range to Ground Range Operator</h3>

<p>
    &nbsp;&nbsp;&nbsp;The operator re-projects images from slant range (range spacing
    proportional to echo delay) to ground range (range spacing proportional
    to distance from nadir along a predetermined ellipsoid). The operator
    works on complex or real slant range product.</p>

<p>Note: The SRGR operator is not required before terrain correcting since terrain corrected results are always in
    ground range.
</p><h4>Major Processing Steps</h4>&nbsp;&nbsp;&nbsp;The slant range to ground range conversion consists of the
following major steps:
<ol>
    <li>Create a warp polynomial of given order that maps ground range pixels to slant range pixels.</li>
    <li>For each ground range pixel, compute its corresponding pixel position in the slant range image using warp
        polynomial.
    </li>
    <li>Compute pixel value using user selected interpolation method.</li>
</ol>
<h4>Interpolation Methods Supported</h4>&nbsp;&nbsp; The operator supports the following interpolation methods:
<ul>
    <li>Nearest-Neighbour interpolation</li>
    <li>linear interpolation</li>
    <li>Cubic interpolation</li>
    <li>Cubic2 interpolation</li>
    <li>Sinc interpolation</li>
</ul>
<h4>Parameters Used</h4>&nbsp;&nbsp;&nbsp;The following parameters are used by the operator:
<ol>
    <li>Source Band: All bands (real or virtual) of the source product. User can
        select one or more bands for producing ground range images. If no bands are
        selected, then by default all bands are selected.
    </li>
    <li>Warp Polynomial Order: The degree of WARP polynomial. It should be a positive integer.</li>
    <li>Interpolation Method: User can select interpolation method used in SRGR conversion.</li>
</ol>
<img style="width: 500px; height: 500px;" alt="" src="images/srgr_dlg.jpg"><br>

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